I completely missed the 'Great Grandmother' bit! Doh!
I helped a friend of mine out earlier this year, he was looking for adoption records for his mum who is in her 80's, she is still living. I left him to it after hopefully pointing him in a direction that might help. I didn't want to get too involved as it's not my family and can be upsetting for the 'new' family about to be contacted. A whole can of worms! Obviously different for a living person.
These are some of the links we came across during our queries/searches.
http://www.bbc.co.uk/radio4/womanshour/03/2007_01_tue.shtml
http://www.norcap.org.uk/home.asp
The BBC link is a program that had been broadcast just before we started to look at his mums case. I personally didn't listen to it but it could contain useful info, there are also a couple of links on the page. (Including one to Norcap)
Norcap is 'supporting adults affected by adoption'. It may also contain helpful advice but again, I didn't delve deeper. I wanted to distance myself from the actual research.
Sue, on the OGFB forum and on here, posted a reply to my query on the OGFB forum which said
"The adoption records are at the Family Record Centre in Inslington , on microfilm. I seem to remember seeing reference to them in November when I was trying to find divorce records for Wilfred. Some of the divorce records are at the National Archives at Kew, so maybe some of the adoption records are too."
Hope something here helps Chrissy.